1883.] Microscopy. go! 
Rose bengale may be used in combination with iodine green 
bleu de lyon (two parts alcohol abs. and three parts aqua dest.) 
and left for a few seconds, then replaced in the absolute alcohol 
preparatory to mounting. 
DOUBLE STAINING WITH ANILINE Dyes.—-Dr. Vincent Harris 
contributes to the last number of the Quarterly Journal of Micro- 
scopical Science (Vol. xxi11, No. 90, p. 292) a valuable article on 
the use of aniline dyes in double staining. His experiments were 
made with solutions of definite strength in regular sequence, and 
confined to blood-corpuscles. The method of experiment finally 
adopted was as follows: The blood was spread in thin layers upon 
cover-glasses and allowed to dry in direct sunlight. The dried 
blood was then wet with a few drops of some dye, and after five 
minutes washed with a slow stream of water from a wash-bottle ; 
it was then dried in the flame of a spirit-lamp and allowed to cool. 
A second dye was then applied in the same way ; and after wash- 
ing the preparation was mounted in balsam, without having re- 
course to alcohol and clove oil. : 
The following combinations of dyes were found to give good 
results : 
Roseine and iodine n. 
Fuchsine and methylene blue. 
Fuchsine and Bismarck brown. 
Methyl violet and methylene blue. 
Roseine followed by iodine green stained the colored corpus- 
cles a bright red, with bluish-green nuclei; and the colorless cor- 
puscles were so stained that three varieties could be readily dis- 
tinguished. = 
Fuchsine and methylene formed a very successful combination. 
The methylene blue was used as a saturated solution in absolute 
alcohol. Pee 
Bismarck brown was prepared as a two per cent solution in 
dilute alcohol. In the nae of this dye, it was found best to im- 
merse the preparation twenty to thirty hours, as the color then 
remains even when passed through alcohol and clove oil. 
An aqueous solution of Hoffman’s violet was used with a dilute 
Spirit solution of Bismarck brown. 
The green dyes are not permanent. The solutions should be 
quite fresh in order to secure successful results, 
* Regarded as identical with Bismarck brown. 
